A610 running problems

Can any one help?

My 610 will not run once it gets unto temperature.

I have put on new earth straps,

unbolted the ecru and ran the car,

New dizzy cap and rotor arm,

New dizzy heat shield,

Heat shield matting behind the ecru,

Lub'd the big electrical connector plugs with that special lug,

Changed the temp sensor,

And still she wont run.

I am just waiting for a new potentiometer (the little red box on top in centre of engine)

But probably that will not make a difference.

Can any one help please?

Also I need to have the Aircon pump reconditioned once I get it running.

I would like to get it to a daily useable condition.

[BIG_MVS]

When you say not run, do you mean misfire or conks out completely?

She cuts out then will not start until she cools down

[stephendell]

Hi lamboman, welcome to the forum.

Have you actually spaced the ECU off from the firewall as well as adding the heatproof layer?

I have J457 JTP down as a total loss in 1996 now repaired and wearing the reg A6 TEN

J456 JTP belongs to John Law and is parked in the garage downstairs!

Hi Stephen.

I did contact you a few years ago but obviously never joined anything till now.

I went to view J457 as it was for sale bout 2/3 years ago and it was a in a terrible untidy state.

No I have just put the matting between ecru and bulk head.

I did unbolt the ecru and place it on the seat but it seemed the same.

Thanks for your replies.

[mettersl]

Have you put it on a diagnostic box? This will tell you what the ECU is seeing and then you should be able to see if the readings are sensible. If not it could be a wiring problem or defective sensors. ART used to rent one out.
To help....
Which temperature sender did you change, air or water?
Is the Map sensor OK??
What does the air fuel ratio tell you (also known as Lambda) when its warming up?
I'd also check the injectors aren't leaking continuously- if so it could be flooding itself when warm.

Can you keep it running on wide throttle settings when warm?

Cheers
lee

Don't know about that lee.

I will get that checked

When the car stops after it is hot, try turning the key to on and listening for the fuel pump to run for a few seconds. Possible problem is the fuel pump relay contacts having high resistance, allowing it to run when cold but failing after running a short while.

Of course the same problem could be the coil opening the secondary when hot.

I hope the distributor cap and button wasn't one of the Italian "Bremi" brand ones that get a sort of conductive silicon type ooze inside them causing misfires on boost.

The throttle potentiometer won't fix your problem.

The fuel pump relays are a good place to start. My gut feeling would be the crank angle sensor. Comes up from the top right of the bellhousing and has a 2-pin grey connector with red and white wires. If that goes open circuit, the engine will die.

With regards the ECU heat - it's as much about allowing the ECU itself to cool as itis about preventing engine bay heat getting at it - so make sure there's an air gap between the ECU and anything else. Don't have any insulation in direct contact with the box.

if the engine still cuts out with the ECU loose and lying flay on the back armrest, then it's probably not the ECU.

I am very grateful of all your advice.

I have replaced the dizzy cap n rotor are with the genuine replacements that I bought from Dave at ART.

The crank shaft sensor and the 3 full pump relays have been replaced (I did that first)

But I will get the wires checked on the crank shaft sensor.

The potentiometer needs replacing anyway as the rubber shrouding over the wires have disintegrated.

The full pump works as a bulb was wired to it to check the circuit and it worked ok.

So I have replaced the following already

Dizzy cap
Rotor arm
Fuel pumps relays
Engine bay temp sensor
Dizzy cap heat shield
Coil pack (the small square bit)
Fuel filters
Earth straps

I have had cleaned the old earth straps and mountings
Had electro lube put on the big round connector from loom to engine bay loom.

I will get the injectors checked.

I was given a big list from Geoff Arthur as a guide and have been going thru' it with the workshop who has the car Lawrence of L G Motors in midsummer norton who is a life long friend.

If he/we can not sort it out then I think I may have to transport it somewhere on a truck.

Andy...........

[BIG_MVS]

Yes take the ecu out of it's cradle and have it on the back seats away from the firewall and see if it still does it.

I also read somewhere that a fault in the wiring for the lambda sensor was at fault with one 610 running issue.

I have replaced the dizzy cap n rotor are with the genuine replacements that I bought from Dave at ART.

The crank shaft sensor and the 3 full pump relays have been replaced (I did that first)

The full pump works as a bulb was wired to it to check the circuit and it worked ok.

Andy...........

When the engine stops you need to check whether you are getting spark still. You should be able to hear the main high pressure fuel pump prime when you turn the key. Injectors are not going to cause the engine to stop, but will cause a misfire and rough running.

I don't know what brand of dissy caps Dave sold, but I wouldn't use anything but a Bosch, being quite easily available as most '80s six cylinder BMWs (eg 635) used the same cap and rotor.

A bulb, unless it is a headlight bulb (55w is approx 4.5A) is not a good choice to test the pump circuit as the pump draws around 8A, and a brake light bulb only 1.5A, so a bad connection may not show up under the lower electrical load.

Well had a little go on the A610 last week.

I let it get to temp with ecru on seat, and after turning it off and leaving for ten mins it would not start again.

I put a direct feed from the battery to the fuel pump yet nothing.

When turning the ignition once it smelt very rich at the exhaust.

I'm having the fuel injectors tested by an injection specialist on Tuesday and if that does not high light the problem I will leave the thing alone as it's wasting my time.

I will not be selling it but I just can't be bothered to keep plugging away at nothing.

I have replaced everything that I have been advised to and always used genuine bits.

Bloody rubbish......

Well I probably have the answer, but having implied I was a retard I don't think I will bother

Well I probably have the answer, but having implied I was a retard I don't think I will bother

touché!

don't tell him..... may he should join the club first then put him out of his misery...... surely he can afford the £30